Alternating-current rectifier.



PATENTED JULY 2, 19o? lNo. 358,574.

AIPLIOATIDH FILED 36.4, 1905.

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WILLIAM eonunennn, or

ALTERNATING-CBENT BECTIFI'E...

Speciicartion of Letters Estant.

Patented July 2, 1907.

lfrppliestion le August 4:, 1905. Serie-l No. 272,650.

To all whom it 'may concern:

Be it known that l, WILLIAM B. CHURCHEP., a citizen of the-United States, residing at Cincinnati, in the county of Hamilton and State oi Ohio, have vinvented 5 certain new and useful lmprovements in Alternating- Current Rcctiiiers, of which the following is o spor fication.

Myl invention relates to improvements in alternating current rectifiers. n

One of its objects is to provide mechanism for producing direct current of low voltage from a source of alternating current.

Another object is to pro vide mechanism for producing W voltage direct currents of character suitable for l5 use in driving dental motors and for similar purposes from a source of alternating current. v

Another object is to provide improved means :tor producing a uniformdirect current from a source of alternating current.4 i A lt further consists in certain details of form, combination and arrangement, all of which will be more fully set forth in the description oi the accompanying drawings, in which;

Figure lis a diagram. of iny improved apparatus. 2,5 Fig.l2 is a central vertical section through the rectifying cell. Fig. 3 is a central vertical section through one of the polarization cells.

l In* the accompanying drawings A represents the primary coil of e. transformer, the terminals of which are connected to the service line Wires or other source of' alternating current,4

B represents the secondary coil in which a current, usually oi lower voltage than that of the line wire is generated by induction. This secondary has two' termintl .connections b bf and an intermediate connection b2. D represents a rcctifying coll in which are a series of'electrodes E E composed of aluminium, and one or more electrodeef o1' platinum, carbon orsirnilar material. The electrolyte may be potassium or sodium phosphate 40 or other substance suitable for 'the purpose. The lines b b. sreconnected cach to one or more electrodes E E While the intermediate connection c leads to encor more polarization cells G, tWo being shown in Fig. l: These cells preferably contain lead electrodes g g immersed in dilute sulfuric acid so as to :form under the action of the current accumulatore or storage cattery cells of small capacity.

H re resents a rela* consist-infT of a. coil. h eurrounin an iron core l.

.l reoresents an armature "infested et l: and adn ted I. l when attracted by the op .te end oi the `core i to close a circuit Z thro' gh the Contact points rm m.

M renresents o. niiet .liht which serves to indicate A. rz the course t ley current.

The motor R or other consumer oi the rectiiiod current is connecte/din circuit :it terminals l, 2, 3, a switch 2 serving to ineke connection select" yely thrmigh line 2 or 3, the voltage 1ocing less beiy 1een terminuls l and 2. than between l and 8, say three volts between l and 2 and iive bolts between l .and 3, whereby the voltag. may be suited to the motor or other use, or the speed ol i the niotor may be regulated.

The dotted line Z indicates that the current may be selectivelyl established through motor .R `fr oui either line 2 or 3 tofline l..

ln order that excessive sparking at the contacts m lm electrode N of aluminium in the rcctiiying cell, co1I is broken, the current has anfziltcrnative path through line n, and the current is interrupted by the resistance of the electrolyte or" the rectifying cell at the surface ci electrode N instead or at contact m, at 'which point there is no sparking, the contacts -m m are not burned or otherwise injured. The unidirectional lout uctuating current produced 1oy the rectiiying cell charges 'the polarization cells GY to such an extent as to cause a steady direct current to he delivered 4to the znotor R, which d.would not run eiliciently on the pulsating current supplied by the rectiiying cell.

The operation is as follows; the alternating current secondary which current is `changed to a unidirectional currentl by the electrodes JJ, which in connection -with the electrolyte permit the passage ol current oi one polarity and suppress current of the opposite polsi When the switch 2 is open and cut out cl circuit tno current passes from b2 by line c through cells G Gf ythence hy line t to pilot light M, which serves to indicate the path oi" the current and also esaresistrtnce to reduce the quantity of current passing. 'llrence the current passes oy lines 7 and l to electrode and by electrodes E E and linescl d to the terminals of coil B. When switch 23 is closed current posses es eli-ove described and also through R, line w coil 12Y and lines I and 8. The action ci coil h howe'v inmediately closes 4contact m rrheretqpfm pilot and resistance l is cut out of circuit and an increased current passes through cells G G to enable them to compensate for irregularities in lthe .rectied current, lthereby delivering a uniform steady current to the motor R. Whentlie switch 2 is opened the current is'hrolren at. m, and any spark hy reason o connect-ioni@ electrodell occurs at the surface oi electrodell Where it can do no injury. Thus while motor t' is out out of circuit, asmall current iowe through cells Gr Gf' 'by nay oi lines c ri through resista-uccisi lines 7 and 8 and. electrodes yF, E Ef.' this and injury thereto or liability oi' the saine to stick to-n .gether or fail to break the Contact, l provide a separate nected in circuit lry'line o. Thus when contact et m,

of the primary induces :In alternating current in the `diietor in electrii'ral 'contact a" pnl-king and current being just euiiicient 'to keep cei'ls 'G GJ charged ready iol use, and not euiiicient to-cause an nndeoirable l generation of gas in said cells, end when mot' circuit 'the contacts m m serve to antomatlcailyreduce 4 the resistance end supply eutii'cient'cilrrent todrive theV motor. y y A I ani time enabletl'io produce a steady direct current suitable for operating dental or other'inotoraoud for other purposfes Where a' eteedydirect 'current Yile re* quired, from a Source'oi alternating current. y And also :to yprovide .durable and reliable @pointue for 'that puroseL.

- aidembl'e modification without departing iromtheprinuciple of my invention. l

` Hering described my invention,` what I- claim is;

1. 1n combinnioir with` e secondary coil inductively energized a, rectilier Having u plurality of asymmetric conductora connectedI io the yrininzile of seid secondary, a neutral conductor in electrical connection witl1`en'intermediate conne tion mi scid secondary, n. polarization cell lrcuit between the ucutril conductor and said inter- A inte conm, tion, n i'clfly in circuit with the consumer ni'tlie rectilied"curl-cnt, and n separate nsyinmetrlc con' with the neutral line to prevent 2: In vcompiI4 condary coil in ductively energfizsexi, u. recliner baiting a plurality of'asymmetricL oondnctors connected to the terminala' ofiaaid secondary, a neutral conductor in electrical connection with'can inter- 4mediatey connection on said secondary, ya plurality of polarii'mtion cells in circuit between the nenti-al conductor und enid intrmediite connection, and a relay in, circuit with the consumer of the rectified current. V f 5' `3.- Irl a mechanism n1 the character indicated, a primary 35 coil. a secondary coil'tenergized thereby and provided with terminal connectlonsend en intermediate connection, a

i'ectiiierrhev'lng'a plurality of asymmetric conductor connected toy the 'terminals of scid secondary, a neutral yconductor yi'nvelectricfll` connection with the intermediate con- '40 nection of the. secondary, a polarization 'cell and a relay connected in circuit suhstiintiallyns specified.

e, In a mechanism. of the character indicated, a primary coil, a secondairy'coil energized thereby .and provided with terminal connections sind an intermediate connection, a 45 'rectifier having a plurality of asymmetric conductore'con4 n ectc'd to the terminale of said secondary, :i neutra] conductor in electrical` connection with the intermediate connection of the secondary, and :i relay, n polarization cell, and un nymmetric conductor connected in parallel 5() -with the relay, said lust named elements being connected in circuit substantially in the manuel' specified` In 'testimony whereof I have aiixed ,my signature in' prcsence'of two wtneoses. y Y

i WILLIAM B. OHURIHER,v :Witnesses: f'

\ v 'TlLnm ihiscunx,

C. W. MILES. 

